I'm looking for performance wise. I do a lot of downloading blueray movies. I usually have a lot of windows and programs running with three of my monitor on. So I usually have my mega manager downloading, a few windows open at the same times, sometimes a movie on one screen, word and excel on another. I'm thinking about adding another 4gb of ram because when I'm downloading, average of 5-10gb at a time, I notice it's using up to 70-80% of my current 4gb of ram. That's when it really slows down my computer. There are times when my computer lag so bad where I just have to restart the computer so that it can clear up my mem and everything is running ok again. So yeah, I usually have a few internet windows open, downloading and uploading, music or movie playing, word and excel all running at the same time. Should I get two of the Caviar blk and do a raid 0 or get one Raptor 300?